Many of my favorite directors (e.g., Ingmar Bergman, Sergio Leone) were drawn to the human face, capturing the souls of their respective characters by way of an applied physiognomy.

Naturally, this wasn't as much an emphasis for Lucas, Kershner and Marquand, but there are numerous instances in which the protagonists/antagonists become credibly human. All without opening their mouths.

My choice bits:

-(TESB-Carbonite Chamber) Leia's determined glare at Vader, as Han is being prepped for freezing. In this context, the silent exchange between the wronged daughter and tyrannical father takes on Greek proportions, suggesting a final, dramatic confrontation in the film(s) to come.

-(ROTS-Mustafar) Anakin's bemused dismissal, when Padme tells him "Obi-Wan knows about us. He wants to help." The look on his face is absolutely unsettling; haughty and borderline psychotic.

ANH - Pretty much all of Han's expressions in the Falcon's cockpit during his conversation with Luke about Leia after they've escaped the Death Star;
ESB - the cutaway to Yoda shaking his head & grunting after Luke has just had his experience in the cave;
ESB - Han while Lando tries his "You truly belong with us among the clouds" line on Leia.

ANH: the bit where Obi-Wan pauses right before telling Luke what happened to his father. (Funny how Guinness' acting choices there gave Lucas wiggle room to completely change the backstory of Luke's father in the next film.)

Piett trying to simultaneously reply courteously to Vader and not be distracted by Ozzel noisily choking to death at the same time. The radio operator or whatever in the background clinches it-he glances at Ozzel's body, up at the viewscreen, and goes back to work completely non-chalantly.

Many of my favorite directors (e.g., Ingmar Bergman, Sergio Leone) were drawn to the human face, capturing the souls of their respective characters by way of an applied physiognomy.

Naturally, this wasn't as much an emphasis for Lucas, Kershner and Marquand, but there are numerous instances in which the protagonists/antagonists become credibly human. All without opening their mouths.

My choice bits:

-(TESB-Carbonite Chamber) Leia's determined glare at Vader, as Han is being prepped for freezing. In this context, the silent exchange between the wronged daughter and tyrannical father takes on Greek proportions, suggesting a final, dramatic confrontation in the film(s) to come.

-(ROTS-Mustafar) Anakin's bemused dismissal, when Padme tells him "Obi-Wan knows about us. He wants to help." The look on his face is absolutely unsettling; haughty and borderline psychotic.

Any preferences?

Yes, this one's indeed awesome.

Several I can think of :

ANH : Obi-Wan's face and awesome expression when he sees Vader waiting for him at the end of the corridor in the Death Star.

ESB : the shot with Luke's tense face when he's engaging Vader in the carbon freezing chamber. Mixture of slight fear and determination, with the eyes wide open.
Han's worried and caring face, when he has just told Luke "be careful" and Luke responds "you too", before he leaves for the air batlle on Hoth.

TPM : Palpatine's surprised and baffled face when the Queen decides to go back to Naboo to take it back from the TF.

-(TESB-Carbonite Chamber) Leia's determined glare at Vader, as Han is being prepped for freezing. In this context, the silent exchange between the wronged daughter and tyrannical father takes on Greek proportions, suggesting a final, dramatic confrontation in the film(s) to come.

-(ROTS-Mustafar) Anakin's bemused dismissal, when Padme tells him "Obi-Wan knows about us. He wants to help." The look on his face is absolutely unsettling; haughty and borderline psychotic.

Any preferences?

You have EXCELLENT taste!

CG Yoda in TPM: The look he gives Mace Windu before Windu says "Bring him before us, then."

Anakin in AOTC: The look he gives Padme after saying "I WISH I could just WISH away my feelings, but I can't." Very accusing in tone.

Sidious in ROTS: "First, go to the Jedi temple..." He seems to get REALLY excited about these words coming out of his mouth. His eyes bulge. Also my vote for creepiest expression in the entire saga.

Han in ANH: His face as C-3PO attempts to introduce himself.

Imperial officer in TESB: There's this one stone-faced dude who's in the background on the Executor. The look on his face is incredibly stupid-looking.

Admiral Ackbar in ROTJ: Not exactly face acting, but the sigh he gives after the Executor goes down. I always assume he's reacting to all the lives being lost at that moment.

Piett trying to simultaneously reply courteously to Vader and not be distracted by Ozzel noisily choking to death at the same time. The radio operator or whatever in the background clinches it-he glances at Ozzel's body, up at the viewscreen, and goes back to work completely non-chalantly.

Yeah, you're right. Maybe not specifically sad over lives lost, but ... sober? I never saw a proud Admiral as he slouches in his seat.

Well, FWIW, Ackbar is arguably the second-most-important character in ROTJ after Luke. It's his battle and plan that's either going to see the Rebellion get vaporized at Endor or deliver the blow that breaks the Empire's political system to pieces. And given that his ragtag collection of funky ships just destroyed the enemy flagship and threw the Imperial fleet into total chaos (it's after Executor goes down that we start seeing Imps fleeing the DS2), sober relief is quite suitable.

Well, FWIW, Ackbar is arguably the second-most-important character in ROTJ after Luke. It's his battle and plan that's either going to see the Rebellion get vaporized at Endor or deliver the blow that breaks the Empire's political system to pieces. And given that his ragtag collection of funky ships just destroyed the enemy flagship and threw the Imperial fleet into total chaos (it's after Executor goes down that we start seeing Imps fleeing the DS2), sober relief is quite suitable.

Agreed. That shot, and the following (Imps fleeing DS2) are very atypical for a big victory moment in Star Wars. Especially for the original trilogy, which was notorious for celebrating the obliteration of faceless, disposable baddies.

TPM comes to my mind.
Valorum after Amidala's vote of no conficence. He seemed disappointet yet in some way relieved at the same time.
And Shmi when Qui-Gon reveals that Anakin has been freed. She's happy for her sun but feels pain.

"This is so wizard! I'm sure you'll do it this time, Annie.""Do what?""Finish the race, of course!""You've never won a race?""Well...not exactly...""Not even finished?!""But Kitster's right, I will this time."(Qui-Gon steps in) "Of course you will."

The comical deadpan look Padme then gives Qui-Gon before darting her eyes back down to Anakin is near priceless.

-------------------------

"Well, look at you, a general, huh?""Oh, well, someone must have told them about my little maneuver at the battle of Taanab.""Well, don't look at me, pal. I just said you were a fair pilot. I didn't know they were lookin' for somebody to lead this crazy attack.""I'm surprised they didn't ask you to do it.""Well, who says they didn't? But I ain't crazy. You're the respectable one, remember?"

And to that Lando flashes what is arguably the most dashing grin of the entire Saga. Maybe ever, in any medium ...in human history.

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"Depends on what, Dex?""On how well your manners are. How big your...pocketbook is ...he he he."

Dex challenges the above with a dastardly good grin himself.

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"An extremely well put together little droid. Without adoubt, it saved the ship, as well as our lives.""It is to be commended. What is its number?""R2-D2, Your Highness.""Thank you, Artoo Detoo."

The camera then cuts to a close up of R2 beaming with childlike happiness as he’s chronologically introduced for the first time into this grand mythology, practically looking right at the audience: "Here I am!" I love it.-------------------------

Finally, for the time being that is, the musically driven, dialogue free scene when Padme lands her ship on Mustafar and spots Anakin approaching from the distance. The close-up to her expression as she takes a moment to look down reveals a brief and quiet sting of emotional despair as she then realizes on some deep level that the man she loves has lost it. Simple but good acting from Portman and a smart visual read by Lucas.

This is followed up by an incredibly effective tracking shot of Palpatine as he stands in the foreground of the platform. Everything about these five seconds is foreboding--particularly McDiarmid's ashen face. For this brief moment, he's revealed as the Stalin of the galaxy.

(If I could post this image, I would. Alas, my computer skills are lacking.)

I agree with previous posters on Qui-Gon's meditation during the duel, Ani's tears and look of self-disgust after the assassinations on Mustafar, Luke's look of utter determination before dueling with Vader on Cloud City, and Han's expression when Leia breaks the news (going from "What the hell?!" to "YES!!!" in about three seconds). I'll add these:

-(TPM) Maul's fierce, smug expression as he looks at Obi-Wan after wounding Qui-Gon. It practically says, "You're next, pal!"
-(ROTS) Ani's expression on Mustafar when he tells Padme how they're going to rule the galaxy; "drunk on the Dark Side" barely covers it. Followed up by his look of quiet rage when he growls at her, "I don't want to hear any more about Obi-Wan."
-(TESB) Luke's look of defeat on the Falcon after the duel. He looks like he's too devastated to live another minute.
-(ROTJ) Han's smile on Endor when he tells Luke & Leia, "Hey, it's me." Followed by the twins' knowing looks; they realize what's about to happen.
-(ROTJ) I like the little smile Luke has when Yoda tells him, "When 900 years old you reach, look as good you will not!" He's glad to hear Yoda make a joke again. Followed shortly thereafter by Luke's expression of loving grief when Yoda passes on.
-(ROTJ) Check out Luke nodding and looking satisfied when Jabba sentences him to the Sarlaac. As I posted on another board, that's clearly what Luke was expecting and wanted. Jedi or not, he was looking forward to taking the Hutt down.
-(ROTJ) I love how Luke is desperately trying to keep from laughing when Threepio reveals that the Ewoks think he's a god, and then when the droid mentions that he's not programmed to impersonate a deity.
-(ROTJ) And Luke giving Ani, Ben & Yoda a friendly wink before turning away is a nice touch. All is forgiven, all's right with the universe.

Sense a pattern with the last few? Mark Hamill has always been underrated for his work in the OT.

JFinally, for the time being that is, the musically driven, dialogue free scene when Padme lands her ship on Mustafar and spots Anakin approaching from the distance. The close-up to her expression as she takes a moment to look down reveals a brief and quiet sting of emotional despair as she then realizes on some deep level that the man she loves has lost it. Simple but good acting from Portman and a smart visual read by Lucas.

I was always of the opinion that Portman is much better at body and face acting than vocal performance.